Insulator pin



A. O. AUSTIN INSULATOR PIN Nov. 6; 1928.

Original Filed May 12, 1920 Wit,

04 44 M jigs;

Patented Nov. 6, 1928.

ARTHUR O. AUSTIN, OF BARBERTOH, OHIO; ASSIGNOR TO AMERICAN NARROW FABRICGOHPANY, or womns'rnn, misssonnsn'r'rs, A CORPORATION or masssonusn'rrs.

INQULATOR PIN.

Original application filed lay 1a, 1920,

This invention relates to pins for support= ing insulators for variouselectrical conduc tors, and has for its object the provision oi devicesof the class named which shall be of improved construction andoperation.

p The invention is exemplified in the combination and arrangement ofparts shown in the accompanying drawings and described in the followingspecification, and it is more particularly pointed out in the appendedclaims.

In the drawingsg p Fig. 1 is-an elevation ofone embodiment oftheinvention with parts in section;

Fig. 2 is an elevation with parts in section of a slightly differentformof the invention; and

Fig. 3 is a similar view of another modification of the invention; V

This is adivision of application, Serial No. 380,826, filed May 12,1920, Patent Number 1,657,340, dated January 24, 1928.. v

Insulators for electrical conductors are supported in a variety of ways,one of the common means being by theuse of pins carried by thesupporting structure andbearm the insulator fitted over the end thereof;uch pins are used for supporting insulators on metal and wooden armsandpole tops and also on various constructions other than regular linewire supports. A pin to meet the requirements to which it is subjectedmust have the necessary mechanical strength to withstand the stressesbrought upon it and should not materially lower the fiashover voltage ofthe insulator or otherwise diminish,

the electrical etliclency of the insulator. The cost of manufactureshould be kept as low as possible and the pin should provide therequired strength without setting up undue stress in the fragilematerial of the insulator The pin should also be. V p I bar stockwithout the loss of material.

which it carries.

adaptable to various conditions which arisein line construction andother electrical installations where insulators are used, and it is alsodesirable that the pins should be so designed that a large variety canbemade from as small a variety of stock as possible.

From the various embodiments ofthe invention shown in the drawin s, itwill be apparent that the small body iameter of pins constructed inaccordance with this invention permits developing the. maximum flashovervoltage value of the insulator since the Serial No 380,826; A Dividedand this application filed March 25, 1926. serial No. 97,187.

surface of the body at a maximum distance from the lower edge of theinsulator itself.

It will also be seen that the supporting base and the body portion ofthe insulator pin are made in separate parts which permits the use of abase having sufficient area so that the cross-arm upon which the base.rests will not be crushed under bending moment. The can sti'uctio'npermits of a balanced arrangement and the same time does not sacrificethe electrical properties of the insulator. In pins having a small baseformed integrally with the pin, the bending moment upon the pin forcesthe edge of the base into contact with the upper face of thesupportingstructure so that where the structure is made of wood,

the fibres are crushed at the edge of the base,

permitting the pin to lean to one side and loosening the connection withthe support. It is impractical to form a pin with an integral base ofsufllcient area to overcome "this diliiculty, for the reason thatif thepin is out from apiece of stock of large diameter the wasteis too greatto justify a sufficient oil pa-nse of base, and if it is undertaken toup set or swage a small r piece of stock to form the base, it isimpossible to expand the mat-erial a suflici'ent amount to give a baseofthe required extent- Such operation also tends to formlaps or flaws inthe metaL Wherethe base is formed separately from the pin and isprovided with means to hold the tw'origidly together, when the pin isinstalled, the base may be made of any desired extent and shape and pinsmaybe standardized sothat uie same,

pins may be used with a large" variety of sup, citing bases. A pin ma besecured to the ase by means of, a. tapeied end fitting in j a taperedsocket and the ta ermay be so proportioned that the pins may be readilymade with aswaging-machine from straightv No finishing operation isnecessary other than the swagi'ng process in order to obtain a good fitfor the base, The taper should be such 7 that the pin will not tend t'O'lift out of the base when a bending moment is applied. and

at the same time the ta er should preferabl be such that the pin wil notbend in the sma 1 sections, th smaller portion of the pin beingreinforced by the base. When the bas'e'an body are assembled they areheld togetheriso that they will work as aunitary structure and the main,body of the pin may be made -shell is tapered, as shown at straightsection or given a taper which will give uniform.strength for thebending moment, or it may be made in stepped diameters, t desired. i

The insulator may be secured to thepin'in a large variety of ways,depending upon conditions. In some cases a lead tip may be cast orpressed on the pin which will form a cushn between the hard metal andthe porcelain. The upper portion of the pin may, some conditions, beprovided with a roughened surface, or with resilient flanges orprojections, toreduce the danger of cracking the insulator underexpansion and contraction of temperature changes. Another method ofsecuring the insulator to the top of the pin 18 to provide theend ot'thepinfwith large or small. threads which can be adapted to 'a fhimble ofsheet material threaded into the insulator. In thisconstruction thethreaded parts may be cone-shaped and, the insulator may be tighteneddown firmly and afterwards the wire groove in the insulator may beproperly alined by turning the pin relative to its supporting basef Thethimbles, however, instead of being cone-shaped may be cylindrical, sothat they can be turned upon the pins to aline the wire grooves-withoutlooseningthe insulator on the pin." Where this arrangement is made, thepin can be'rigidly attached to the supporting base. Under mostconditions, however, thepin and base will be separable which will permitcombinations of vaious forms of pins with different kinds of bases sothat the proper arrangement may be secured for a large variety ofconditions.

In Fig. 1 a composite pin isshown comprising a central rod 51 having anouter strengthening tubular shell 52 surrounding the rod.

The rod and shell each forms a reinforcement for the other and thetwoco-operate toform an exceedinglystrongpin. The shell 52 is pressed intoshapev from a straight tubular memberand atthe same time secured inplace upon the central r0d51. The compression of the tubular member toform a taper will, of course, cause a gradual thickening of the wall ofthe pin from the top of the base portion to the, top of the pin, asshown in the drawing. Depressions 53 may be previously .formedin therod51 at the points of contact "between therod and the shell, so that themetal of the shell will be forced into the de pressions duringtheformingoperation and thusinsure firm connection between the rod andthe outer shell. The lower end of the 54, for engaging atapered socketmember 59 and the ends of the rod 51 are threaded, as shown at 55 and56, for connection with means for securing the pin on its support andwith means for securing the insulator upon the pin, respectively. v

In Fig. 2 a pinis shown similar to that illustrated in Fig. 1, exceptthat a portion of under member liavin shape and tapered to fit asocketmember 85 formed on'a base 86. An internal reinforcing sleeve 87is arranged within the tubular member 84 to strengthen the pin adjacentthe base and to provide material for a threaded openingfor receiving thethreaded end of a bolt 88. lVhere the lower ends of the pins arethreaded for receiving the threaded ends of standard bolts, it will beapparent that the pins may be secured to various sizes of crossarms bymerely substituting bolts of different standard lengths.

I claim:

1. An insulator pin comprising a tubular member having a hodyportiontapered towards its upper end, an oppositely tapered base portion and asupport for said tubular member having a tapered socket therein forreceiving said tapered base portion and hav-' ing a flange extendingradially from said base portion, the opening in said body portion beingalso tapered toward the upper end of said pin.

2. An insulator pin comprising a tubular member having an elongated bodyportion tapered toward its upper end, the opening in said body portionbeing also tapered toward theupper end, a shorter oppositely taperedbase portion, a supporting base having a tapered socket therein forreceiving said base portion, and a reinforcing member disposed withinsaid base portion,

the opening in said ,body member being larger than said reinforcingmember at the junctionof said body 1 and base portions.

3. An insulator pin comprising a tubular 0 the opposite ends thereof.swaged-lnwart ly to provide an upwardly tapering elongated body portionand a lower oppositely tapered base portion with the maximumdiameter ofsaid pin at a point adjacent the top of said base portion, the walls ofsaid tubular member being gradually thickened from the point of maximumdiameter toward the top of said pin, and a support for said tubularmember having a tapered socket therein for receiving said tapered baseportion and having a flange extending radially from said base portion.

4. An insulator pin comprising a tubular member having an elongatedupper body portion tapered inwardly toward the top thereof, abaseportion tapered inwardly toward the bottom thereof, and a reinforcementdisposedwithin said base portion and tightly held in place therein bythe walls of said base portion, said walls being spaced away from saidreinforcement between the ends of said pin. 7

5. An insulator pin comprising a tubular member having a centralreinforcing rod extending therethrough, said tubular member beingfixedly secured to said rod against relative longitudinal movement ofsaid rod and ber being spaced from said rod intermediate the ends ofsaid tubular member but tapered inwardly to engage said rods at oppositeends of said tubular member, the upper tapered end of said tubularmember being longer than the lower tapered end thereof.

8. An insulator pin comprising a tubular member having a reinforcing rodextending therethrough, said tubular member being spaced outwardly fromsaid rod intermediate the ends thereof but tapered inwardly to engagesaid rod at opposite ends of said tubular member, and a supporting baseengaging the lower tapered end of said tubular member, said rod beingextended beyond said tubular member at the opposite ends thereof.

9. An insulator pin comprising a tubular member having a reinforcing rodextending therethrough, said tubular member being tapered inwardlytoward the opposite ends thereof, a supporting base for receiving thelower tapered end of said tubular member, and having the upper extremitythereof substantially registering with the maximum diameter of saidtubular member, said tubular member being spaced outwardly from said rodat the point of maximum diameter of said tubular member.

10. An insulator pin comprising a tubular member having a reinforcingrod extending theret-hrough, said rod having irregularities on thesurface thereof adjacent opposite ends of said tubular member, saidtubular member being swaged inwardly to engage said rod and to conformto the irregularities on the surface thereof to provide firmconnectionbetween said tubular member and rod at opposite ends of saidtubular member, said tubular member being spaced outwardly from said rodintermediate the points of connection with said rod and being graduallytapered toward the opposite ends of said tubular member from anintermediate point. 11. An insulator pm comprising a tubular memberhaving a reinforcing rod extending thercthrough, said. tubular memberbeing,

spaced outwardly from said rod at apoint between the ends of saidtubular member and gradually tapered toward said tubular memer atopposite sides of said point and closely engaging said rod at the endsof said tubular member, said rod being extended beyond said tubularmember, and a supporting base having a socket receiving the lowertapered end of said tubular member.

In testimony whereof I have signed my name to this specification on this20th day of March, A. D. 1926.

ARTHUR o. AUSTIN.

CERTIFICATE OF CORRECTION.

Patent No. 1,690,392. Granted November 6, 1928, to

ARTHUR 0. AUSTIN.

It is hereby certified that the above numbered patent was erroneouslyissued to "American Narrow Fabric Company, of Worcester, Massachusetts,a corporation of Massachusetts, whereas said patent should have beenissued to "The Ohio Brass Company, of Mansfield, Ohio, a corporation ofNew Jersey", said corporation being assignee by mesne assignments of theentire interest in said invention, as shown by the records ofassignments in this office; and that the said Letters Patent should beread-with this correction therein that the same may conform to therecord of the casein the Patent Office.

Signed and sealed this 11th day of Decemher' AaD.1.928.

M, J. Moore, (Seal) Acting Commissioner of Patents

